Preparation of hydrophobic modification of sodium carboxymethyl cellulose and pH-sensitive hydrogel

This paper presents that the hydrophobic modification of sodium carboxymethyl cellulose(CMC-Na) is carried out by esterifying agents of C10,C12,C14,C16 and C18 acyl chloride in n-heptane medium.The optimal reaction condition is established according to the discussion of the ratio of reactants,reaction temperature and time.The hydrophobicly modified sodium carboxymethyl celluloses(Ln-CMC-Na) are prepared under the molar ratio of 0.08∶1 of esterifying agents to CMC-Na.The surface active properties of HLB value,surface tension and critical micelle concentration are determined respectively.Having taken the aluminum chloride as crosslinker,a pH-sensitive hydrogel is formed by Ln-CMC-Na solution.